my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Portable Osciloscope (Page 1)

This topic comprises 2 pages: 1  2

Author Topic: Portable Osciloscope Fernando Cavallero Film Handler Posts: 6 From: Buenos Aires Argentina Registered: Mar 2007 posted 07-30-2008 10:12 PM                     Hello, I´ve been using my old CRT scope for many years. It has a 2 by 2 inches screen and is very light and portable. I´m thinking to upgrade to a digital one. Which are the best options to work in the field? The azimuth in some digital scopes is terrible (many dots without a shape) I don´t know if should buy a "USB scope" to use with a notebook or a handheld style... Thanks!  |  IP: Logged Robert Minichino Master Film Handler Posts: 350 From: Haskell, NJ, USA Registered: Dec 2005 posted 07-30-2008 11:08 PM                        I'm not so sure a digital oscilloscope is an 'upgrade' from an analog CRT scope. I have both and I still find myself going back to the CRT scope for certain tasks. I've heard good things about Tek's Digital Phosphor scopes, but they're a bit out of my price range.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-30-2008 11:23 PM                     I have yet to see a pc based scope that works like a CRT scope for a digital alignement I still use my old leader  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-31-2008 06:55 PM                     The more expensive Tektronix and I'm sure other high end digital scopes work well with all the waveforms we typically view. Big bucks though! PC based scopes just don't cut the mustard... or was that wind??? Mark  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 07-31-2008 08:29 PM                        Both Fluke & Tek sales angineers tried to properly display the Dolby Digital waveform and struck out (badly). I would e-bay a 1970's Tek for 150-200 bucks. Louis  |  IP: Logged Fernando Cavallero Film Handler Posts: 6 From: Buenos Aires Argentina Registered: Mar 2007 posted 07-31-2008 09:47 PM                     I agree with Robert that digital is not an upgrade. But the dammed "modern technologies" are pushing us to the digital domain. Can you believed that mi CRT is 30KHZ bandwith! and you can see the video sygnal perfectly.  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 07-31-2008 11:21 PM                        Out of curiousity, what does a digital oscilloscope do that an analog scope dosn't? (I've only ever used analog CRT models.)  |  IP: Logged Robert Minichino Master Film Handler Posts: 350 From: Haskell, NJ, USA Registered: Dec 2005 posted 07-31-2008 11:49 PM                        All sorts of cool stuff, like displaying the waveform before the trigger event, fancier triggering modes, fancy math on waveforms, FFT spectrum analysis. Plus they cost more and only the hugely expensive ones are intuitive for analyzing signals with transients.  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 08-01-2008 05:42 AM                     I think the biggest feature of a digital oscilloscope is having a useful one-shot trigger with persistent display. So you can watch a non-periodic event from the moment it happens, and not have to worry about only having a split-second to see it before the phosphors disappear. (Yes, there are specialized analog scopes that solve this problem, too, but they're not exactly commonplace.) Another handy feature is that you can download the trace to a computer, either so you can extract precise data from the trace, or so you can have a handy screenshot without the added aggravation of a camera. They also seem to have less useful user interfaces, with many more buttons that are modal and overloaded with multiple functions --jhawk  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-01-2008 05:49 AM                        The up side is that they are very good at showing the outside of a waveform; very bad at the "grass" inside it. Too bad, but that is required for DD set up. Louis  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 08-01-2008 09:21 AM                        So, essentially, a digital scope doesn't really offer much, if any, benefit for typical cinema use (sound alignments), correct?  |  IP: Logged Andres Briano Expert Film Handler Posts: 162 From: Buenos Aires, Argentina Registered: Jan 2008 posted 08-01-2008 10:51 AM                        I would never go to a PC-based scope.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-01-2008 11:20 AM                     quote: Louis Bornwasser Both Fluke & Tek sales angineers tried to properly display the Dolby Digital waveform and struck out (badly). I don't know Louis... The days of real Tektronix field engineers are long over. The old guys koew theor stuff... the new bunch are more sales then engineering. There are indeed digital scopes that do work. They are widely used in broadcast today and more than capable of displaying anything you throw at them... just expect to spend upwards of 7 grand to get one that'll do the stuff we need. The less expensive Tektronix digital and Fluke scopes just don't cut it for more than general purpose... and they do work well for digital circuits which is the world we now live in. I do however agree that Ebaying a used 100 mhz Tektronix scope is the best way to go for most tecnicians... but ya have to be careful there too!! It can be more difficult to get parts for later Tektronix CRT models than it is the earlier models. Mark  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-01-2008 08:57 PM                        Agreed! We bought 5 identical scopes for about $175 each. (Also bought 3 spare Abacus analyzers, just before they stopped making them.) Louis  |  IP: Logged Noel Mackisoc Film Handler Posts: 8 From: Newton, NJ, USA Registered: Jun 2008 posted 08-31-2008 01:58 PM                        I bought an OWON PDS5022S-BAT for $395.00 new from their dealer here in NJ. 25MHz. Two x1/x10 probes. Battery/AC. Very light and nice large screen. Intuitive--up and running in about 5mins out of the box.You can look it up on their site www.owon.com.cn. It's not a Tek or Fluke, but it works well, easy to use, and I'm happy with it. Have used for a-chain, Dolby reader alignment and a few other tasks in and out of shop. I'd give it 4+*. Hope this helps.  |  IP: Logged

All times are Central (GMT -6:00)

This topic comprises 2 pages: 1  2

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.